Journal for pulverizing mill rollers



Dec. 20, 1932. E, NEEDHAM 1,891,355

JOURNAL FOR `PULVERIZING MILL ROLLERS Filed Jan. 5. 1929 2 Sheets-Sheet 1 will." WW

c. E. NEEDHAM vJ'OIJRNAL FOR PULVERIZING MILL ROLLERS Dec. 20, 1932.

Filed Jan. 5, 1929 2 Sheets-Sheet g Patented Dec. 20, 1932 UNITED STATES PATENT oFFIcE CHARLES E. NEEDHAM, OF CHICAGO, LLINOIS, ASSIG-NOR TO THE RAYMOND BROTHERS IMPACT PUIJ'VIERIZER C0., 0F CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS JOURNAL FOR PULVL'RIZING MILL ROLLERS Application ledranuary 5, 1929. Serial N'o. 330,501.

in the patent to Raymond et al., No. 1,573,191,

granted Feb. 16, 1926. Ina mill of .this type,

"a plurality of pulverizing rollers are pivotally suspended in a circular series from a rotating frame or spider, the rollers swinging out by centrifugal force against the inner surface of a fixed circular bull ring, whereby the material caught between the ring and rollers is pulverized.

The present invention relates to an improved form of journal support for one of these rollers, including an improved self-con- -tained lubricating system for the bearings,

and an improved means for supporting the renewable roller on a permanent supporting sleeve.

One object of this invention is to provide improved means for rotatably supporting a pulverizing roller upon a non-rotatable shaft,

which is suspended in a substantially upright position. Y

Another object is to provide an improved self-contained circulating lubricating system for supplying lubricant to thebearing surfaces between the roller assembly and the non-rotatable shaft, the circulation of the lubricant being enforced by the centrifugal -force developed. by the bodily revolution of the rollers about the fixed central axis of the mill. Y

Another' object is to provide improved means for supporting a removable and renewable annular roller upon a supporting sleeve which is permanently mounted upon the non-rotatable shaft. This means embodies the use of wedge-shaped pockets inthe roller and adjusting and supporting bolts having wedge shaped heads engaged in the pockets, whereby tapered engaging surfaces on the roller and sleeve are drawn into engagement with one another.

Other objects and advantages of this invention will be moreapparent from the following detailed description of certain approved forms of apparatus embodying the principles of this invention. Y

In the accompanying drawings:

Fig. 1 is a central vertical section through one of the roller assemblies and adjacent parts of the mill structure.

Fig. 2 is a diagrammatic plan view, designed to illustratethe centrifugal forces de- 1 veloped by the revolution of the roller, whereby the oil circulation is enforced.

Fig. 3 is a sectional perspective showing a portion of the annular roller.

Fig. 4 is a sectionalV perspective through the upper bushing.

Fig. 5 is adetail elevation of one of the wedge-shaped bolts and the portion of the roll-er with which it engages.

At 1 is shown a portion of thek rotating spider or frame which supports the rollers,

axis of the mill, which is indicated at 2 in Fig. 2. The outer portion ofthe spider 1 comprises a plurality of yokes 3 arranged at spaced intervals about its circumference. In each yoke 3 is rotatably supported a trunnion shaft 4. The rocker 5 comprises a Vsplit collar 6 formed on one side thereof and ,adapted to be clamped about the trunnion shaft 4 by means of bolts 7. The tapered upper end portion 8 of the roller-supporting shaft 9 is adapted to be received in the central vertical tapered opening 10 in rocker V5. The upper end 11 ofv shaft 9 is threaded to receive the nut 12, which is screwed downinto engage-Y ment with the top of rocker 5 todraw the tapered portion 8 of the shaft into tight engagement with the tapered opening 10 in the rocker. Nut 12 is locked in place by the bolt 13 threaded through the split portion 14 at one side of the nut. A lre'y15 secured in the shaft 9 engages a key-way 16 in the Vrocker 5 to prevent relative rotation between l A these members.

A central oil passage 17 extends axially vthrough shaft 9 from top to bottom thereof,

toA add` new oil through the upper end of-'lOcv this spider rotating about the fixed central f 7 arrow a, in Fig. 2,

passage 17. The lower' portion of passage 17 is preferably enlarged, as indicated at 18, to form a reservoir of greater capacity for the oil.

Below the upper tapered portion 8, the shaft 9 is externally cylindrical, but the upper cylindrical portion 19 is fof-somewhat f smaller diameter than the lower cylindrical ortion 20 there being an inwardl extend! Y' t collars 24 and 26 being formed with a series of mating openings, through which bolts 27 provided with nuts 28 are secured, so as to clamp the twosleeves 23 and 25 in engagement with one another.

The lower sleeve 23 ris open at its upper vend, but closed at its lower end 29, so as to form a well 30rextending below the lower end of non-rotating shaft 9.v Abushing 31 is interposed between sleeve -23 andshaft 9,

this bushing having an outwardly extending collar or flange 32 at its upper end, secure to the sleeve 23 by pins 33. The upper surface of collar or flange 32 engages the under surface of collar 22 on the shaft, so as to limit the upward movement of sleeve 23 with relation to the shaft.

The upper sleeve or housing 25 has a smaller substantially cylindrical upper portion 34, between which and the shaft is interposed the bushing 35. The lower portion of sleeve 25l isflared outwardly to form a skirt Y36 enclosing a chamber 37 which extends downwardly about the supporting collar 22. ange 26 is formed on the lower end of skirt 36,. The bushing 35 has a flange or collar 38 at its lower end extending outwardly into` the chamber 37 and secured to the sleeve 34 by pins 39. A pair of thrust rings 40 yand 41which carry the load, are positioned in the chamberv37, the upperring 40 being secured to the sleeve 25 of the rotating assembly by meansofthe pins 39, and the lower ring 41 being secured to the non-rotating collar 22 on the shaft 9, by means of pins 42.

The bushing 35 has a thicker' upper portion 43 adapted to extend inwardly and cngage the portion 19 of shaft 9 of smaller diameter, and this portion is formedv with an inner spiral groove 44 which opens toward the shaft and terminates Vat its lower end against the beveledsurface21on the shaft. This groove or thread 44 is of suchdirection and vpitch that when theA roller assembly is rotated about shaft 9 in the Vdirection of the The any oil or other lubricant that may find its way between the portion 43 of bushing 35 and the shaft will be caught and carried downwardly by this spiral groove. A packing or sealing means, consisting of a plurality of composition washers 45, held in place within the upper portion `of f'sleeve 25 .'by a split 'metal ring'46, bears against the shaft to prevent dust entering between the top. of the rotatingassembly and the shaftf A-skirt 47,-f'orm'edfon tlifeflow'er4 end of rocker 5, extends down over the upper end of sleeve 25 into proximity to an outwardly 'ext-ending collar 48 formed on the sleeve. i

An oil duct or passage 49 is rformed in the shaft 9 and extends inwardly and down'- wardly from its outer end, which opens from the inwardly beveledlsurface 21 of the shaft, to itslo-wer-end whichV connects with the central oil passage 17. This oil duct49 is formed verizing roller 51 is providedwith a corre` spondingly tapered inner surface 52 so that the roller may be drawn into snug engagement with the sleeve. The upper portion of roller 51 is formed with a plurality of pook# ets 53, opening into the tapered inner pas-v sage 52 and also through the upper face of the roller, the lower portions 54 of these pockets being wedge shaped withv the large end off the wedge at the bottom, as indicated in Figs. 3 land 5. A plurality of bolts 55 have wedge shaped lower ends 56, which. are adapted to be positioned in the wedge shaped ends 54 of the pockets, the upper threaded ends 57 of these bolts passing through mating openings in the sleeveI anges 24 and 26 and receiving nuts 58, whereby the supporting bolts 55 are drawn upwardly, so as to draw the roller 51 into snug engagement with the tapered surface on sleeve 23. The wedge shaped lower ends 56 of the bolts will engage the upwardly tapering side surfaces of the.

pockets 54 so that the bolts willbe assured of at least a two-point contact with the roller.` This avoids the necessity for careful machin-` ssI worn. The `bolts 55 may be inserted in the pockets in the new roller and re-used as in the'irst installation. y

The roller 51 is adaptedl to engagethe bull CIE the shaft.

ring 59, which is fixed to the stationary outer frame 60 of the mill. Material caught be-v tween the ring 51 and bull ring 59 will be pulverized in the well known manner. It will be apparent that as the roller assembly is revolved bodily about the central axis 2 f the mill in the direction of the arrow b in Fig. 2, centrifugal force will tend to throw the roller 51 outwardly in the direction of the arrow c, thus forcing the roller into engagement with the bull ring and causing it to rotate thereon in the direction of the arrow a.

Assuming that the reservoir 18 and the well have been filled with lubricant inserted through the passage 17, the rapid rotation of the roller assembly, including the sleeve 23 about the central axis of shaft 9, will tend to throw the oil in well 30 outwardly and cause it to flow up between the rela tively rotating bearing surfaces on the shaft and bushing 31, this oil being replaced by oil from reservoir 18, which is forced downwardly .by gravity. This film of oil will flow up until it reaches the chamber 37, wherein centrifugal force will throw the oil out so as to fill this chamber about the relatively rotating thrust rings and 41. This oil, being replaced by new oil flowing up from the well 30, will pass in between the bearing surfaces of thrust rings 40 and 41 and thence upwardly between the bushing 35 and the shaft 9. This upwardly flowing oil will force the oil ahead of it inwardly along the beveled surface 21. Any oil that continues to How upwardly will be caught in the spiral channel 44 and carried downwardly against the beveled surface 21. There is also a centrifugal force acting on this oil that has reached the bevel surface 21, this force being due to the bodily revolution of the roller assembly about the central axis 2 of the mill. There is a force tending to throw this oil in the direction of the arrow c, Fig. 2. There is also a force of inertia opposing the movement of the roller and the oil and acting in the direction of the arrow d. The combination of these several forces will act in some such direction as c and tend to concentrate the oil at the side of the shaft opposite this arrow e. The oil duct 49 is positioned substantially in line with the direction of action of this, centrifugal force, so that this force will tend to make the oil flow inwardly through this duct to the central passage 17 in The exact direction in which this force acts may vary, and if the duct 49 is located any where in that half of the shaft which faces toward the central axis 2, but preferably in the quadrant that faces the direction of revolution b of the shaft, the oiling system will operate satisfactorily. The oil which flows over the upper beveled surface 21 will be carried by centrifugal force against the outer surface of the rotating bushing 35,

' but will beheld against further 'upward travel, due to the bushing rotating about the central axis of the shaft 9, this force opposing the inward movement of the oil along tapered surface 21. As this accumulated oil is carried around opposite the mouth of duct 49, part of this oil will be caught and forced inwardly by centrifugal force through the duct 49 and into the central passage 17, wherein it will iiow down by gravity to join the oil supply in reservoir 18. Any oil that may find its way up along bushing 35 about the tapered surface 21 will be caught in channel 45 and carried downwardlyl to this .beveled surface and thence forced to flow inwardly through duct 49. It is desirable that a very small quantity of oil find its wayk past the bushing 43, so as to lubricate the engaging surfaces of the packing 49 and shaft 19. The amount of oil used in this manner will be comparatively small. t will be noticed that there is a continuous circulation of the oil downwardly through the shaft 9 and upwardly between the shaftand the bushing and thence inwardly through duct 49 to the oil supply within the shaft. This continuous circulation of the oil is enforced by the combined action of gravity and the centrifugal forces developed by rotation of the roller about the central axis of the shaft and the bodily revolution of the roller about the cenf tral axis 2 of the mill. The oil supply may be replenished when necessary by removing the plug 17 at the upper end of the passage 17 :The overlapping surfaces of the shaft and bushing 35 at the beveled surface 21 will permit ra certain amount of wear to take place at one side of the bushing and still provide a pocket in which oil will be trapped and carried around to the duct 49, despite the fact f f that a clearance will be developed at that sideV of the shaft opposite the point rwhere the wear takes place.

I claim:

1. In an apparatus of the character described, a shaft, means for suspending the shaft in a substantially vertical position, the

shaft being held in the suspending means e against rotation about its own axis but being bodily revoluble about a fixed vertical axis, Y

there being a central lubricant passage extending axially through the shaft, a roller assembly rotatably supported on the shaftand enclosing the lower end of the shaft so as to form a lubricant well below the shaft, the

lubricant passage in the shaft communicatingv shaft above the shoulder, meansV for sealing ilo ice,

gg positioned that centrifugal force will cause the joint between the-upper end of this bushfrom the surfaceof the shoulder on the shaft to the central oil passage, the duct being so oil to flow inwardly through this chiot.

2. In an apparatus of the character described, a shaft, meansfor suspending the shaft in a substantially vertical position, the shaft being held in the suspending means against rotation about its own axis but being bodily revoluble about a fixed Vertical axis, there being acentral lubricant passage extending axially through the shaft, a roller assembly rotatably supportedon the shaft and enclosing the lower end of the shaft so as to form a lubricant well below thD shaft, the lubricant passage in the shaft communicating with this well, the upper portion of the shaft being of a smaller diameter so as to form an inwardly extending and upwardly facing annularvshoulder on the outer surface of the shaft, a bushing interposed between the roller assembly and shaft and rotating with the rollei, this bushing having an upper portion of smaller inner diameter so as to engage the shaft about the shoulder, means for sealing the joint between the upper end of this bushing and the shaft, and an oil duct leading from the surface of the shoulder on the shaft to the central oil passage, this duct being positioned in the side of the shaft which faces the fixed axis about which the shaft revolves.

8. In an apparatus of the character described, a shaft, means for suspending the shaft in a substantiallyI vertical position, the

shaft being held in the suspending 'means against rotation about its own axis but being bodily revoluble about a fixed vertical axis, there being a central lubricant passage exe tending axially through the shaft, a roller assembly rotatably supported on the shaft and enclosing the lower end of the shaft so as to form a lubricant well below the shaft, the lubricant passage in the shaft communicating with this well, the upper portion of the shaft being of a smaller diameter so as to form an inwardly extending and upwardly facing annular shoulder on the outer surface of the shaft, a bushing interposed between the roller assembly and shaft and rotating with the rollei, this bushing having an upper portion of smaller inner diameter so as toengage the shaft above the shoulder, means lorY sealing the joint between the upper end of this bushing and the shaft, there being a spiral `groove formed in the inner surface Vof the upper portion of the bushing with its lower end terminating at the shoulder and its open side engaging the shaft, and-an oil duct leadingV from'the surface ofthe shoulder on the shaft to the central oil passage, the duct being so positioned that centrifugal force will cause oil to flow inwardly through this duct.

4. In an apparatus of the character deassesses scribed, a shaft, means for suspending the shaft in a substantially vertical'position, the

shaft being held in the suspending means form an inwardly extending and upwardly facing annular shoulder on the outer surface of the shaft, a bushing interposed between. the roller assemblyy and shaft'and rotating with the roller, this bushing having. an upper portion of smaller inner diameter so as to engage the shaft above the shoulder, means for sealing the joint between the upper end ofV y this bushing and the shaft,`there being a spiral groove formed in the inner surface of the upper portion of the bushing with its lower end terminating at the shoulder andy its open side engaging the shaft, and an oil duct leading from the surface of the shoulder on the shaft to the central oil passage, this duct being positioned in the side of the shaft which faces the fixed axis about which the shaft revolves.

5. In an apparatus of the character described, means for suspending the shaft in a substantially vertical position, the shaft being held in the suspending means against rotation about itsv own axis-but being bodily revoluble about a fixed vertical axis, the shaft being formed with an upper portion of re duced diameter so as to provide an upwardly facing annular shoulder connecting the outer cylindrical surfaces, the shaft also being formed at a location beneath this shoulder with an outwardly extending annular flange, there being a central oil passage extending axially through the shaft, a roller assembly comprising a plurality of connected members Y vsupported for rotation about the shaft-andA suspended thereon by the annular flange,

there being an oil well in one of these members below the shaft with which the centrall passage communicates, there being a plurality of bushings secured in the assembly and engaging the shaft, the upper bushing vhaving a portion of smaller inner diameterengaging the shaft above the shoulder, means for sealing the joint between the upper portion of sage, this duct beinglocated in that side of the shaft which faces the fixed axis about which the shaft revolves.

6. In an apparatus of the character (lescribed, means for suspending the shaft in a substantially vertical position, the shaft being held in the suspending means against rotation about its own axis but being bodily revoluble about a fixed vertical axis, the shaft being formed with an upper portionof reduced diameter so as to provide an upwardly facing annular shoulder connecting the outer cylindrical surfaces, the shaft also being formed at a location beneath this shoulder with an outwardly extending annular ange, there being a central oil passage extending axially through the shaft, a roller assembly comprising a plurality of connected members supported for rotation about the shaft and suspended thereon by the annular flange, there being an oil well in one of these members below the shaft with which the central passage communicates, there being a plurality of bushings secured in the assembly and engaging the shaft, the upper bushing having a portion of smaller inner diameter engaging the shaft above the shoulder, means for sealing the joint between the upper portion of this bushing and the shaft, and an oil duct in the shaft extending from the surface of the shoulder to the central passage, this duct being located in that side of the shaft which faces the fixed axis about which the shaft revolves.

CHARLES E. NEEDHAM. 

